1. Field of the Invention
The present invention relates to an electrophotographic copying machine. More specifically, the resent invention relates to an electrophotographic copying machine having an editorial function capable of performing "moving" mode in which an original image is moved based on a positional information or data designated by a position designating means such as an input pen or a mouse.
2. Description of the Prior Art
An electrophotographic copying machine of this kind is disclosed in Japanese Patent Application Laying-Open No. 87466/1984, for example. In this copying machine, after an original is set on a position detecting board for image editing and a position designation is made by an input pen, the original is moved on an original table and then a copying process is executed. When "moving" mode is set, a moving distance designated by the input pen is converted into a rotation angle of a photosensitive drum. Then, the photosensitive drum is rotated based on the converted rotation angle.
In the above-described prior art, if a moving distance is simply converted into a rotation angle of the photosensitive drum, it is impossible to avoid influences of "excess or play" of a driving system of the photosensitive drum. If an oil membrane of a metal is run out, for example when the copying machine was stopped for a long time and restarted, a driving load will increase in comparison with the case of a good lubricating. In this case, the excess or play such as a backlash of gears functions to make the rotation angle of the photosensitive drum to be small, therefore, it is impossible to form or output an image which is precisely moved in accordance with the moving distance as inputted.